The machine that changed the world – the IBM PC – turns 30 this week

IBM may have been out of the personal computing business for some time, but 30 years ago it kicked off a revolution by bringing small, affordable computers to the masses.

Yeah, there were other PCs before the IBM PC – originally known by its numeric moniker, the 5150 – but the strategy of using off-the-shelf, interchangeable parts to build a personal computer was an innovative one at the time. Ironically, that approach also proved to be IBM’s undoing, as it quickly spawned a slew of competitors who copied its design and sold systems for much less.

In a post on the official Microsoft blog, Frank X. Shaw – the company’s VP of corporate communications – waxes nostalgic about the event, which also happened to put his company on the map.

But the introduction of the IBM PC was a defining moment for our industry. Once IBM entered the market with a system running the Microsoft Disk Operating System, MS-DOS, our industry really began to realize the dream of a PC on every desk and in every home. (Aside: my first computer, which I still own and which boots on MS-DOS 5.1, was the IBM Personal Portable).

Shaw links to the original press release for the 5150, which sold for $1,565. According to this inflation calculator, that would be $3,704.77 in today’s dollars. Clearly, it was not cheap at the time, but it bore the nameplate of the biggest computer company of the day, and that helped validate a market pioneered by Apple, Commodore, Tandy, Osborne and others.

For that price, you got a computer that used either 5.25-inch floppy drives, a tape drive or – if you could afford it – a 5.25-inch disk drive. ItsIntel 8088 processor ran at just 4.77 MHz. You could max out the memory at 256 kilobytes, though the base model came with just 16 KB.

Rather than design its own components, IBM gathered the parts from other vendors and assembled them into a case that made upgrades relatively easy. Its only real proprietary component was its BIOS, which controls the low-level functions of the computer.

Clone-makers sprang up almost immediately, assembling their own set of parts and reverse engineering the BIOS. Many of them couldn’t quite get that part right, resulting in models that were not quite compatible with the software applications that were being written for the IBM PC. Some even advertised themselves with percentages of compatibility. And yes, people actually bought systems labeled “75 percent IBM Compatible”, though I suspect they didn’t do that more than once.

I don’t think there’s any question that this machine changed the world, created vast fortunes and altered history’s course. Our technologically rich society stands on the shoulders of the IBM PC, which helped democratize computing. From the Internet to smartphones to digital media, key innovations were made possible by the foundations it laid down.

And even though it’s a competitor to companies that still adhere to IBM PC design, even the fact that Apple on Wednesday became the most valuable public company can, in part, be chalked up to the success of the IBM PC.

Want to see the 5150 in action? Sit back and wait for it to boot from a floppy disk in this video.